The man who shot the video wanted to remain anonymous but agreed to allow us to use his first name, John, for the story.

John said he was walking his dog near Whitetail Drive when he heard a woman screaming. “At first, it sounded like someone was yelling at a child or at a dog,” John said. As he got closer to Cooper he saw her with a stick in her hand. “She looked like she was going to strike him.”

John got out his iPhone and began recording the confrontation and 15 seconds into shooting the video Cooper can be seen hitting the man with a stick.

Moments after the assault, John intervenes and asked the woman, “Ma’am is there a problem?” Cooper responds, “Yes, this damn man is trying to assault me.”

According to John, he called 911 to report the assault. Castle Rock Police said they took action after FOX31 Denver turned the video over to detectives.

Johnson's family confirms Dennis, 67, suffers from Alzheimer’s and dementia.

The assisted living center where Cooper worked fired her after she was arrested by police.

Cooper told the Judge that she was tired that day, but it doesn’t take away from her actions. She apologized to Johnson and his family.

The state has since revoked her nurses' aide license. Cooper said she no longer works and a caregiver.